Bzzz, bzzz! Who is not familiar with the short, buzzing dings of a smartphone, claiming our attention everyday? And how can a user stay tuned for offers, posts, or even news and emergencies, without having to constantly check a screen? There are just too many apps for a person to handle, and this is where the push notifications come to save the day.

A brief history

Going back to 2003, the engineers of BlackBerry, the leading mobile device of the Canadian company RIM, introduced what was to change our mobile user experience forever: push services. At the time, it was an innovative concept, allowing us to get notified automatically from our mobiles whenever a new email popped in. What a great relief from the stress that something important could go unnoticed! Now the user could receive, read and reply immediately to incoming mails and the BlackBerries became a must-have for every businessperson, until a new player entered the field in 2009.

That was the iOS 3.0, an update for Apple’s iPhone operating system, with its own implementation of notifications, the Apple Push Notification Service. The APNS’s mission was not only to help users keep track of their mailbox, but also for a whole bunch of other apps. If we didn’t want to miss out on breaking news or the new game a friend on social media played, we only had to download the app, and leave the rest to the APNS.  As with any other successful idea, push notifications were soon supported from the competitor of iOS, the Android, and together they transformed our interaction with mobile phones.

Google went one step further in 2013, when it replaced the previous notification system with Google Cloud Messaging. Although initially targeted for mobile phones, GCM was also featured on Google’s web browser -Chrome-, bringing push notifications to our desktops. In 2016, GCM was renamed to Firebase Cloud Messaging, and along with the fresh name came new, additional functionalities, all in a simple and easy to use package.

Until today, push notifications were responsible for helping us cope with the, oh so many, different sources of information that crave our attention. A life without them would be steeped in F.O.M.O (fear of missing out), filled with unanswered calls, pending messages, missed concerts and offers. But is it really so?

Image by Jamie Street on Unsplash

Perception from Users

Although notifications seem like a great way to contact and engage users, for a large number of them, the constant buzzing is more of an annoying distraction. Based on recent survey, sending two or more notifications per week can lead to 37% of the users opting-out of push messages for this particular app, while the 31.1% would completely stop using the app, if they received 6-10 messages per week. So, flooding the screens with notifications is definitely not the way to go.

Another decisive factor for the success of push notifications is their actual value. How is this defined? From the app’s functionality and type. For example, in ride applications like Uber, notifications come in extremely handy, as the user doesn’t have to constantly check the phone or wait in the rain for the driver. The Uber app just sends a push notification when the car arrives to the meeting spot and the user knows they are ready to leave. For social media apps however, it is totally different. These apps were designed for the free-time scrolling, not for constantly alerting their users with trivialities; something far from useful or informative.

Graph by localytics

How to take advantage of push notifications in ChildRescue

Not all push notifications are helpful and when too frequent, they could even discourage users from using an app. Success depends on the way notifications are used towards their target groups. The key words are: personalisation, discretion and relevance. If an app’s notifications don’t want to be muted, apart from containing meaningful content, they must signify an exceptional event for the user: an exclusive offer in a nearby store, a long-awaited response or a social emergency.

ChildRescue will leverage the technology of push notifications to reach out to the community. By sending notifications about a missing child, citizens will be informed and mobilised. With their feedback, the time until the child is found could be reduced. However, what’s the use in notifying users far away from the suspected location of the missing child? Most probably after they see the location, they will find it irrelevant and won’t pay attention to the rest of the details. And as we have seen, regularly sending irrelevant messages to a user can lead to complete disengagement. Although ChildRescue notifications will deliver an important message, relevance to the user still matters.

Location will stand out as one of the most valuable triggers for notifications in ChildRescue. Location-based notifications in ChildRescue will have a twofold role: keep users engaged and interested, while increasing the possibility to receive a real lead from them. There are a few different techniques already used in geolocation marketing, which could assist ChildRescue.

Two of the most common are:


Geo-targeting is the method of reaching users based on their IP address, rather than GPS location. It was a forerunner of mobile. As it is not very precise, it is most commonly used for targeting broader regions, like a whole city.


The mobile era of geo-targeting. It uses GPS address and is updated while the person is on the move. A virtual perimeter of specified radius (geofence) is set and whenever a user goes through this, an alert is triggered. Although the radius can be as wide as a whole city, this method is more suitable for smaller regions (e.g. streets, neighbourhoods).

By SpyToMobile (, GeoFence, CC BY-SA 4.0



ChildRescue aspires to engage in its social mission as many users as possible. With the help of notification technology this has become easier than ever. However, notifications can become annoying if not used properly. ChildRescue will therefore make use of them in a privacy-aware manner, and always respecting users’ rights over their personal data. The best practices and location-based techniques will be employed, to ensure that no notification will go unseen, as this time they will be for a really good reason.

More info on push notifications and location-based techniques: